[PasswordManager] Correctly switch password backends.

src/lib/autofill/passwordmanager.cpp

@@ -126,6 +126,17 @@ PasswordBackend* PasswordManager::activeBackend() const
     return m_backend;
 }
 
+void PasswordManager::switchBackend(PasswordBackend* backend)
+{
+    if (!backend) {
+        return;
+    }
+
+    m_backend->setActive(false);
+    m_backend = backend;
+    m_backend->setActive(true);
+}
+
 bool PasswordManager::registerBackend(const QString &id, PasswordBackend* backend)
 {
     if (m_backends.contains(id)) {

src/lib/autofill/passwordmanager.h

@@ -67,6 +67,7 @@ public:
 
     QHash<QString, PasswordBackend*> availableBackends() const;
     PasswordBackend* activeBackend() const;
+    void switchBackend(PasswordBackend* backend);
 
     bool registerBackend(const QString &id, PasswordBackend* backend);
     void unregisterBackend(PasswordBackend* backend);

src/lib/preferences/autofillmanager.cpp

@@ -117,17 +117,20 @@ void AutoFillManager::changePasswordBackend()
         Settings settings;
         settings.beginGroup("PasswordManager");
 
+        PasswordBackend* backend = 0;
         foreach (const QString &key, backends.keys()) {
             if (backends[key]->name() == item) {
+                backend = backends[key];
                 settings.setValue("Backend", key);
                 break;
             }
         }
 
         settings.endGroup();
+
+        mApp->autoFill()->passwordManager()->switchBackend(backend);
     }
 
-    mApp->autoFill()->passwordManager()->loadSettings();
     QTimer::singleShot(0, this, SLOT(loadPasswords()));
 }